This piece contains spoilers

Christopher Nolan has said himself that the simplest explanation of Memento for audiences is that it is a noire-esque tale, told by its protagonist in reverse. Although he prefers a different structural concept. “If you draw out the time-line, it is indeed a hairpin. If you order the material chronologically, the black and white material moves forwards, and in the last scene switches around and goes backwards to the colour scene. So there is this hairpin turn.”

“Breaking this idea down, this is how the film concludes. The final backwards-moving colour segment of the film begins with Leonard’s (Guy Pierce) screech to a halt outside the tattoo parlour (where he will significantly request Teddy’s (Joe Pantoliano) licence plate number to be inscribed on his leg, setting him on a journey that will ultimately lead to Teddy’s death – as seen at the film’s outset). When the scene closes, Nolan takes us back to the black-and-white sequence, where Leonard leaves the motel, meets Teddy, and heads to the derelict hallway, chronologically just before the tattoo parlour scene. As Leonard takes a polaroid of the dead Jimmy Grantz, the film fades into colour, as the polaroid develops, at one of the film’s most elegant but understated moments. Leonard, unsettled by Teddy’s revelations in the derelict hallway, decides to choose him as the next John G., copying his licence plate down, knowing he will soon forget his murderous intent. The next step? The tattoo parlour, of course, and the skid to a halt.”

“You can never find out where you are in the time-line, because there is no time-line,” says Jonah Nolan, writer of the short story that inspired brother Christopher Nolan’s screenplay. “If it was a straight-backwards film, you could just take that two-dimensional time-line and flip it over, but you can’t do that with this film. Later on down the line, you realise that this film doesn’t run back; it’s a Möbius strip.”

Effectively the film is one continuous twist from start to finish. One of the keys is understanding the parallel subjective view of the reverse colour sequences, told from Leonard’s point of view in the here and now; and the objective view of the forward moving black and white, where he is an unreliable narrator. Here is Christopher Nolan to explain the structure, in an excellent 18 minute analysis by Eyes On Cinema, complete with blackboard. Now, pay attention…